Does infection affect amputation rate in chronic critical leg ischemia?

Background: Aim was to analyze the association between local infection and amputation rate in patients with chronic critical limb ischemia (CLI) with or without successful revascularization.
Patients and Methods: We performed a retrospective analysis of 56 consecutive patients with 57 critically ischemic legs seen at the University Hospital Bern. Patients with CLI were selected if ischemic lesions and follow-up of more than 2 months were documented. Infection was suggested when 2 of the following criterion were present: temperature > 37 degrees C, C-reactive protein > 50 mg/L, leukocytes > 10 x 10(3)/microliter ("2 of 3" criterion), or a putrid secretion was documented ("secretion" criterion).
Results: In patients with successful revascularization (n = 39), there was a significant shift from 10.3% major to 33.3% minor amputations (Chi Square p value = 0.014) as compared to patients without or with failed revascularization (n = 18) with 44.4% and 11.1% (Chi Square p value = 0.008), respectively. An infection was suggested in 22 of 53 limbs (41.5%) according to the "2 of 3" criterion, and 30 of 57 limbs (52.6%) satisfying the "secretion" criterion. Both criteria, were significantly more common in patients undergoing amputation as compared to patients without amputation (p = 0.001). Multiple lesions were more common in patients with major amputations (p = 0.026).
Conclusion: Successful revascularization effectively reduces major amputations and leads to healing of ischemic ulcers. Secondary foot infections are frequent. Infections are associated with a significantly higher rate of minor and major amputations, also in patients with successful revascularization, and should be treated adequately as well as in time with antibiotics.